This invention relates to bus structures for racks supporting stacked electrical equipment such as power converters, and more specifically to a plug-in bus structure for carrying high-current DC either applied to an output from the electrical equipment as well as data for controlling the equipment.
Power supplies for providing DC power to large electronic installations such as mainframe computers conventionally consist of a number of individual power converters that are stacked one above the other on separate chassis in racks that may be enclosed in equipment cabinets. It is desirable for these racks to contain AC power lines and data and DC buses to which a converter may be connected merely by pushing its chassis into the rack. Because the converters used in a given installation would normally have the same shape and size horizontally but could be of varying heights, it is necessary for a bus system built into the rack to allow a converter to be plugged into it at substantially any vertical level. Prior art power system equipment bays have required that the location of each piece of plug-in equipment be predefined usually at the time of initial configuration of the system. Each piece of equipment must also be interconnected and traditionally this is done with a xe2x80x9cpower shelfxe2x80x9d for the converter equipment, in which each power shelf supports three or four converters and a series of cables are used to interconnect multiple power shelves to a common distribution panel. Individual equipment not supported by power shelves must be interconnected using discrete cable assemblies.
Because of space and cost considerations, it is desirable to integrate the data bus with the DC bus, yet assure a reliable contact between the converter and the buses while preventing any possibility of short-circuiting the electronic circuitry during insertion or removal of an individual converter.
The bus structure of the present invention fulfills the requirements set out above by providing a pair of parallel, vertically extending DC bus bars that define between them a vertically extending slot. Along the sides of the slot, insulating strips are inserted into the DC bus bars. These strips carry the data bus bars on their outer faces. The converter chassis supports a long data connector which fits into the slot and carries the data contacts, and a pair of shorter male DC connectors each of which plugs into a corresponding vertical female contact groove in the front face of each of the DC bus bars. The data contacts are encased in an insulating shroud in the data connector that prevents them from coming into contact with the DC bus bars during insertion or removal of the converter chassis. Also, the mutual spacing of the data contacts and data bus bars is such that the data contacts cannot accidentally bridge two data bus bars.